1. Field of the Art
The present embodiments relate to a method for reducing chatter in an extrusion process.
2. Description of Related Art
One of the challenges faced with polymer profile extrusion, particularly at higher outputs, is so-called “chatter” caused by binding and hesitation of the extrudate as it passes through the calibrator/sizers. Repeated binding and release of the extrudate in the calibrator/sizers can leave lines and/or marks along the profile surface. At lower extrusion rates, it may be possible to adjust extruder conditions to solve the problem. At higher output rates chatter can become more pronounced and more difficult to control via extrusion process adjustments.
Heat stabilizers are commonly used in PVC formulations to improve the thermal stability of the PVC during processing. Heat stabilizers also protect the PVC against long-term thermal degradation. Examples of commercially available stabilizers include, for example, methyltin mercaptide stabilizers, and butyltin mercaptide stabilizers. Some heat stabilizers also help to improve chatter in PVC extrusion processes.